Heating system.



A. CASTELLAZZI.

HEATING SYSTEM.

APPLICATION FILED APR.26. 1913.

Patented Sept. 5, 1916.

2 SHEETS-SHEET 1.

Inventor:

- I U I Witnesses;

Wf ZUQmAA/ A. CASTELLAZZI.

HEATING SYSTEM.

APPLICATION FILED APR. 26. 1913.

1 1 97,342. Patented Sept. 5, 1916.

2 SHEETS-SHEET 2.

INVENTOR. aria/m Wa 4' By m g -0M ATTORNEY.

ARTURO CASTELLAZZI, 0F MILAN, ITALY.

HEATING SYSTEM.

Specification of Letters Patent.

rammed Sept. 5, 1916.

Application filed April 26, 1918. Serial No. 763,824.

To all whom it may concern:

Be it known that I, ARTURO CASTELLAZZI, a subject of the King of Italy, residing at a via Enrico Cernuschi Milan, in the Kingdom of Italy, have invented certain new and useful Improvements in Heating Systems, of which the following is a specification.

As is known, the drawback of steam heating installations in general is the great difficulty in obtaining a central or common regulation of the heat radiated by the radiators provided in the rooms to be heated. The method in accordance with the present invention obviates the said drawback in connection with steam heating installation. The method consists essentially in arranging on. the main steam piping adjacent the outlet of the steam from the boiler, a device whose function is to stop the steam supply from time to time and the operation of which comprises the following two stages: (1) Rapid shutting olf of the steam supply pipe and maintaining the pipe closed for a more or less long period of time, as desired; (2) opening of the supply pipe until the maximum is reached, during a certain period which should be in proportion to the first period and to the result it is desired to attain.

The new method of regulation hereinafter described is for a low pressure steam heating installation, and it is assumed that the latter is in full operation. All the radiators are completely or nearly filled with steam at about atmospheric pressure; the piping, however, contains steam at a pressure slightly higher. Assuming that the shutting ofl apparatus which was open until now, is operated and dividing the efiects thereby obtained into two stages, then the following occurs:

First stage.'l[he apparatus shuts 0d the steam supply and maintains it shut for a certain time. As soon as the closure is efiected then the steam contained in the pipes, expands and progresses toward the radiators. It is to be noted as an important fact that this process is effected under a practically equal pressure for all the radiators, owing to the manner in which these installations are constructed and regulated. in practice, the radiators farther away from the boiler, obtain more steam in proportion to their surface than the nearer ones, owing to the farther radiators, which normally obtain steam at a lower pressure than those located nearer to the boiler, being provided with larger inlets under otherwise similar conditions. In any case, the pressure of one atmosphere is shortly attained in the plpmg and the supply stops, but as the condensation in the radiators continues, air enters into them through the discharge pipmg and said air replaces the steam which has condensed; consequently the steam level in the radiators, that is to say the separating surface between air and steam, the specific weight of which is less, gradually rises until a certain level is reached at which moment the second stage begins. During the first stage the pressure of the steam in the boiler, the outflow of steam from the boiler being Stopped, has gradually increased up to a certain maximum value which depends upon the duration of the first stage and the intensity of the combustion and which can therefore be determined at will by predetermining the duration of the cycle of the apparatus.

Second stage.-The regulating device opens the steam outlet up to the maximum and exerts on the latter a certain variable throttling action. The pressure in the primary increases gradually until the normal pressure is reached everywhere. At the beginning the pressure is naturally much higher at the entrances of the radiators situated nearer the boiler than in the farther ones. The difference of pressure has an influence exceeding that of the difi'erence of the areas of inlet and therefore more steam is obtained by the radiators located nearest the boiler than by those farther away. This is'exactly the opposite to what occurs at the beginning of the first stage and as the opening of the steam Supply can he efi'ected as desired at a slower or quicker rate and can thus exert an influence on the length of the period of return to normal conditions, then it is possible to attain a certain balance between the said occurrences.

When the. normal working pressure is reached everywhere then steam is supplied to all radiators under normal pressure and the separating surface between steam and air in the same, drops continuously. The shutting ofi apparatus, however, is regulated in such manner that the shutting oif takes place before each radiator is completely filled with steam. Then the process starts again.

With reference to the manner in which the shutting off apparatus operates the opening and closing of the steam supply pipe, the slow openlng of the steam supply pipe by a controlling valve is necessary in order to counterbalance the lack of uniformity in the steam supply to the radiators during the period when the valve has been maintained closed. The rapid shutting off of the valve is also required to prevent any lack of uniformity in the distribution of the steam to the radiators, which would take place if the shutting off were slow, and allow the installation to be supplied at a pressure lower than the normal. These advantages are increased by varying the duration of the periods during which the pipe is maintained open, inasmuch as it is thereby possible to admit more or less steam to each radiator according to its superficial area, for a predetermined period of time so as uniformly to vary the heating effect of the separate radiators.

The drawing illustrates by way of example means for carrying the method into practical effect. 1

In the drawings: Figure 1 shows a cam controlled valve closed, Fig. 2 shows the same open, Fig. 3 is an end elevation of the cam for controlling the valve, Flg. 4 is a diagrammatic view of an apparatus for carrying the method into effect and for securing the safety of the installation. Fig. 5 1s a diagrammatic view of a heating installation showing the relation thereto of the apparatus according to the invention.

The device designated as a whole by the numeral 1 consists of an ordinary flap valve. The cam A B (Figs. 1, 2 and 3) represents the device for controlling the valve. The cam A'is uniformly rotated at a periodical speed (duration of the periodzone revolution) by means of a motor of any suitable kind. This cam completes one revolution in the time necessary for the regulating apparatus to effect one stage. The periphery of the cam may be varied by displacing in the known manner the sector B on the disk A. The roll-carrying end of a lever C bears upon the cam and is pivoted at D and actuates the steam control device by means of the rod E. By altering the periphery of the cam, the duration of the periods can also be altered as well as the speed of opening and of shutting-oil. The length of the rod E, can be varied as desired by means of a sleeve F provided with right and left hand threads.

A rod carrying an adjustable counterweight G is mounted on the pivotal axis of the flap valve and serves to keep the valve closed against the steam pressure until the time is reached at which the cam acts to open the valve. Everything is so arranged that in the case of a stoppage of the apparatus in the shut-oil position owing to any unforeseen occurrence and should the ressure in the boiler exceed a certain limit, then the pressure of thesteam would oyercome the action of the counterweight, open the valve and thus provide an outlet for the steam.

For maintaining the safety of the apparatus a safety siphon may be provided in installations in which the low pressure steam is supplied directly from the boiler, for the purpose of permitting the steam to reach the main piping directly from the boiler without having to traverse the regulating apparatus when the boiler pressure exceeds a certain normal value.

The arrangement shown in Fig. 4, consists mainly of a siphon the cross sectional area of which is equal to that of the steam main piping. Both arms of this siphon, one of which H is vertical and the other K inclined, communicate with the main steam piping, namely, on either side of the regulating apparatus. The arm K has a small extension at its lower end and communicates with a pipe L which extends upwardly and opens into a receptacle M of suitable capacity. This receptacle is provided with an overflow pipe N which dlscharges into the collecting funnel O for the condensation water. In this arrangement the proportions of the parts are such that the vertical distance between the highest point of the receptacle M and the point P where both arms H and K meet, which gives the height of the column of water, is equal to the pressure at which it is desired that the safety apparatus should start operating. It is evident that when the siphon is filled with water, a hydraulic seal is thus formed as long as there is water above the point P; when the level SiIlKS lower than the point P the steam will pass through the inclined arm the position of which favors its passage; the water contained therein sinks and is driven back through the pipe L, into the receptacle M; if the latter does not suflice to receive the whole of the water, then it flows over into the collecting funnel O for the condensation water and thence into the boiler. The passage of steam from the latter to the main piping is thus effected, and the system can operate, as if the regulating apparatus were not present and as if the piplng were always open.

The function of the receptacle M is to decrease the oscillations of the water in the siphon, especially during the operation of the regulating apparatus so as to avoid upon the opening each time of the latter, water rushing back into the collecting funnel O and emptying the siphon. Further, in order to prevent discharges of water from both arms of the siphon H K into the horizontal piping they must be of such length that the level, which is attained in them by the water in the state of equilibrium, is at a sufiicient distance from that part of the horizontal piping where the arms K and H join the said piping.

Referring to Fig. 5, showing a diagrammatic view of a low pressure heating installation provided with apparatus according to the invention, on the right hand side the steam reaches the radiators from below, and on the left hand side from above, a being the boiler Z, Z the regulating apparatus, H, H the safety siphons, d, d steam piping, e, e the radiators, f, f Water pipes, g, 9 air exhausts.

It is evident that the described method of regulating is not only applicable to steamheating installations. alone but also to any other heating installations such as steam-air heating, steam-water heating and the like.

What I claim and desire to secure by Letters Patent of the United States is 1. A method of regulating low pressure steam heating installations from a central station involving in its practice alternately maintaining and interrupting the supply of steam at regular intervals, by periods of in terruption and of supply in predetermined mutual proportion to one another; the periods of interruption being sufficiently short to prevent any sensible coldness of the radiators of the system and the duration of the periods of steam supply being such as to allow of conditions approximating to those of normal working being reached.

2. A method of regulating lowpressure steam heating systems involving in its practice the gradual admittance and rapid shutting off of the steam independently of the conditions of Working within the steam generator and in such manner as to give rise to cycles in continuous succession, each cycle comprising a period of admittance and a shutting off period, the duration of the period of maximum admittance being variable from a fraction of the duration of the cycle to the entire duration of the same.

3. A method of regulating low pressure steam heating systems involving in its practice the gradual admittance and rapid shutting off of the steam at predetermined and variable intervals and, should the steam pressure exceed a predetermined limit, the passage of the steam direct from the source of supply to the heating installation.

4'. A method of regulating low pressure steam heating systems involving in its practice the gradual admittance and rapid shutting off of the steam at predetermined and variable intervals and, should the steam pressure exceed a predetermined limit, the displacement of a liquid and the passage of the steam direct from the source of steam supply to the heating installation.

In testimony whereof I afiix my signav ture in presence of two witnesses.

ARTURO CASTELLAZZI.

Witnesses BRATO- SALVATIR, CARLO CARRANQA. 

